This invention relates to resin-impreganated fibrous stiffening materials, for example, the type described and disclosed in U.S. Pat. Nos. 4,081,917, issued Apr. 4, 1978 and 4,162,583, issued July 31, 1979. Those patents, assigned to the assignee of this invention, describe articles, techniques and devices for use in initially flexible and deformable shank stiffener elements which, once applied to the bottom of an insole, then can be activated and cured to a hardened, stiff shank element. The material normally is available in reeled-up lengths of fiberglass impregnated with an activatable resin material, all encased within an impermeable sleeve. While in many shoemaking applications, the material may be used without stripping the sleeve, there are some instances in which it may be desired to use the impregnated fiberglass rope without the sleeve. This invention relates to an improved method and apparatus for stripping the sleeve and severing a length of the impregnated fibers. For example, the strip and severed material may be used in practicing an invention as described in an application filed of even date herewith by Jules N. Allard and entitled "Techniques for Stiffening Shoe Insoles".